Hearing device providing spoken information on the surroundings

ABSTRACT

A navigation system includes a hearing device configured to be head worn and having loudspeakers for emission of sound towards ears of a user; a GPS unit for determining a geographical position of the system; a sound generator connected for outputting audio signals to the loudspeakers; and a processor configured for selecting Points-Of-Interest in a vicinity of the system, and controlling the sound generator to output the audio signals that represents spoken information on the selected Points-Of-Interest in sequence.

RELATED APPLICATION DATA

This application claims priority to, and the benefit of, European PatentApplication No. EP 12176120.9, filed on Jul. 12, 2012, pending, theentire disclosure of which is expressly incorporated by referenceherein.

FIELD

A new personal navigation system is provided, comprising a GPS-unit anda hearing device having an inertial measurement unit for determinationof orientation of a user's head and configured to emit spokeninformation on points of interest in the vicinity of the user of thepersonal navigation system.

BACKGROUND

Typically, present GPS-units guide a user towards a desired destinationusing visual and audible guiding indications. For example, presentGPS-units typically displays a map on a display screen that includes thecurrent position of the user, typically at the centre of the displayedmap, and a suitable route drawn on the displayed map towards a desireddestination accompanied by spoken instructions, such as “turn left atthe next junction”.

Conventional GPS-units typically includes a database with a variety ofparticular locations denoted points-of-interests or POIs. POIs aretypically shown on the map with an icon indication the particular typeof the POI in question at the geographical position of the POI.

Typically, POI categories include: Restaurants, Hotels, ShoppingCentres, Industrial Estates, Police Stations, Post Offices, Banks, ATMs,Hospitals, Pharmacies, Schools, Churches, Golf Courses, Low Bridges,Historic Sites, Camping & Caravan Sites, etc.

Typically, the POI database includes information on POIs, such as thetype of POI, the name of the POI, longitude and latitude of the POI, theaddress of the POI, possible phone numbers, etc.

Some conventional GPS-units are configured for containing audio toursguiding the user along a specific route with MP3 audio files associatedwith respective POIs along the route and played automatically when theGPS-unit is within a certain distance from the POI in question. Theaudio tours with MP3 audio files are downloaded into the GPS-unitbeforehand.

SUMMARY

A method of navigation is provided comprising the steps of

determining the geographical position of a person with a GPS unit,selecting Points-Of-Interests in the vicinity of the user, andcontrolling a loudspeaker worn by the user to output spoken informationon the selected Points-Of-Interests.

A personal navigation system is provided, comprising

a hearing device configured to be head worn and having loudspeakers foremission of sound towards the ears of a user,a GPS unit for determining the geographical position of the system,a sound generator connected for outputting audio signals to theloudspeakers, anda processor configured forselecting Points-Of-Interests in the vicinity of the system, andcontrolling the sound generator to output audio signals with spokeninformation on the selected Points-Of-Interests in sequence.

The hearing device may accommodate an inertial measurement unitpositioned for determining head yaw, when a user wears the hearingdevice in its intended operational position on the user's head.

The personal navigation system may comprise one or more pairs of filterswith Head-Related Transfer Functions selectively connected in parallelbetween the sound generator and the loudspeakers for generation of abinaural acoustic sound signal emitted towards the eardrums of the userand perceived by the user as coming from a sound source positioned in adirection corresponding to the respective Head-Related TransferFunction.

The processor may be configured for determining directions towards eachof the selected Points-Of-Interests with relation to the determinedgeographical position and head yaw of the user, selecting pairs offilters with Head-Related Transfer Functions corresponding to thedetermined directions, and controlling the sound generator forsequentially outputting audio signals with spoken information on theselected Points-Of-Interests in sequence through the respective selectedpairs of filters so that the user hears spoken information on thePoints-Of-Interests from the respective directions towards thePoints-Of-Interests.

Thus, a personal navigation system is provided that relies oncommunication to the user of audible information on the surroundings ofthe user. The information is communicated with the hearing device,preferably with a sense of direction so that audible informationrelating to a specific site proximate the user will be perceived by theuser to be emitted by a sound source located at the site in question.

For example, the user may arrive at a historical site, such as a townsquare, with many sites of interest. With a user interface of thepersonal navigation system, the user may then request the personalnavigation system to provide an introduction to the site at the townsquare, and the user may specify the types of POIs of interest to theuser, e.g. historical sites. In response to the user request, thepersonal navigation system then identifies the relevant POIs, andsequentially narrates information on the identified POIs, and thenarrator will sequentially be perceived to be positioned at therespective POIs.

In this way, the user is provided with spatial knowledge about thesurroundings and the need to visually consult a display of thesurroundings is minimized making it easy and convenient for the user tonavigate to geographical locations, the user desires to see or visit.

The user may then request the personal navigation system to guide theuser to a selected geographical position, such as a selected POI fromthe POIs just presented in sequence to the user. Thus, preferably theprocessor is also configured for determining a direction towards aselected geographical destination with relation to the determinedgeographical position and head yaw of the user, and controlling thesound generator to output audio signals guiding the user, and selectinga pair of tilters with a Head-Related Transfer function corresponding tothe determined direction towards the selected geographical destinationso that the user perceives to hear sound arriving from a sound sourcelocated in the determined direction.

The personal navigation system may contain a database of POIs in a waywell-known in conventional hand-held GPS-units.

Some or all of the POI records of the database of the personalnavigation system include audio files with spoken information on therespective POI.

Alternatively, or additionally, the personal navigation system may haveaccess to remote servers hosting databases on POIs, e.g. through aWide-Area-Network, or a Local Area Network, e.g. providing access to theInternet.

Thus, the personal navigation system may have a wireless antenna,transmitter, and receiver for communicating over a wireless network witha remote server accommodating a database with information on POIs, e.g.including audio files with spoken information on some or all of thePOIs. The wireless network may be a mobile telephone network, such asthe GSM network.

The wireless network may provide a link through an Internet gateway tothe Internet.

The personal navigation system may transmit the current position of thesystem to the remote server and requesting information on nearby POIs,preferably of one or more selected categories, and preferably sequencedin accordance with a selected rule of priority, such as proximity,popularity, user ratings, professional ratings, cost of entrance,opening hours with relation to actual time, etc. A maximum number ofPOIs may also be specified.

The server searches for matching POIs and transmits the matchingrecords, e.g. including audio files, to the personal navigation systemthat sequentially presents spoken information on the matching POIs withthe hearing instrument.

In the same way, the personal navigation system may communicate with anavigation enabled remote server and request navigation tasks to beperformed by the remote navigation enabled server instead of performingthe navigation tasks locally by the personal navigation system. Thepersonal navigation system may communicate position data of the currentposition, e.g. current longitude, latitude; or, the received satellitesignals, and position data of a destination, e.g. longitude, latitude;or street address, etc., to the navigation enabled server that performsthe requested navigation tasks and transmits resulting data to thepersonal navigation system for presentation to the user.

The hearing device comprises one small loudspeaker, or a pair of smallloudspeakers, designed to be held in place close to the users ears. Theloudspeaker, or pair of loudspeakers, is connected to the soundgenerator. The inertial measurement unit, or part of the inertialmeasurement unit, may be accommodated in a housing together with oneloudspeaker of the hearing device; or, the inertial measurement unit mayhave parts accommodated in separate housings, each of which accommodatesone of the pair of loudspeakers.

The hearing device may be an Ear-Hook, In-Ear, On-Ear, Over-the-Ear,Behind-the-Neck, Helmet, Headguard, etc, headset, headphone, earphone,earbud, ear defender, earmuff, etc.

Further, the hearing device may be a hearing aid, e.g. a binauralhearing aid, such as a BTE, a RIE, an ITE, an ITC, a CIC, etc, binauralhearing aid.

The hearing device may have a headband carrying two earphones. Theheadband is intended to be positioned over the top of the head of theuser as is well-known from conventional headsets and headphones with oneor two earphones. The inertial measurement unit, or part of the inertialmeasurement unit, may be accommodated in the headband of the hearingdevice.

The hearing device may have a neckband carrying two earphones. Theneckband is intended to be positioned behind the neck of the user as iswell-known from conventional neckband headsets and headphones with oneor two earphones. The inertial measurement unit, or part of the inertialmeasurement unit, may be accommodated in the neckband of the hearingdevice.

The personal navigation system may also comprise a hand-held device,such as a GPS-unit, a smart phone, e.g. an Iphone, an Android phone,etc, e.g. with a GPS-unit, etc, interconnected with the hearing device.

The hearing device may comprise a data interface for transmission ofdata from the inertial measurement unit to the hand-held device.

The data interface may be a wired interface, e.g. a USB interface, or awireless interface, such as a Bluetooth interface, e.g. a Bluetooth LowEnergy interface.

The hearing device may comprise an audio interface for reception of anaudio signal from the hand-held device.

The audio interface may be a wired interface or a wireless interface.

The data interface and the audio interface may be combined into a singleinterface, e.g. a USB interface, a Bluetooth interface, etc.

The hearing device may for example have a Bluetooth Low Energy datainterface for exchange of head jaw values and control data between thehearing device and the hand-held device, and a wired audio interface forexchange of audio signals between the hearing device and the hand-helddevice.

Based on received head yaw values, the hand-held device can display mapson the display of the hand-held device in accordance with orientation ofthe head of the user as projected onto a horizontal plane, i.e.typically corresponding to the plane of the map. For example, the mapmay be displayed with the position of the user at a central position ofthe display, and the current head x-axis pointing upwards.

Selected Points-Of-Interests may also be indicated on the displayed mapin addition to the spoken information presented to the user. AdditionalPoints-Of-Interest for which spoken information is not presented to theuser may also be displayed on the map, preferably with icons thatdistinguishes these Points-Of-Interest from the selectedPoints-Of-Interest.

A user interface of the hand-held device may constitute the userinterface of the personal navigation system or a part of the userinterface of the personal navigation system.

For example, the user may use the user interface of the hand-held deviceto select a specific Point-Of-Interest that the user desires to visit ina way well-known from prior art hand-held GPS-units.

The user may calibrate directional information by indicating when his orher head x-axis is kept in a known direction, for example by pushing acertain push button when looking due North, typically True North. Theuser may obtain information on the direction due True North, e.g. fromthe position of the Sun on a certain time of day, or the position of theNorth Star, or from a map, etc.

The hand-held device may display maps with a suggested route to thedesired geographical destination as a supplement to the aural guidanceprovided by the personal navigation system. The hand-held device mayfurther transmit spoken guiding instructions to the hearing devicethrough the audio interface as is well-known in the art, supplementingthe other audio signals provided by the personal navigation system.

The hand-held device may accommodate the sound generator of the personalnavigation system.

The hand-held device may accommodate the processor, or parts of theprocessor, of the personal navigation system.

The hand-held device may accommodate all or some of the one or morepairs of filters with Head-Related Transfer Functions of the personalnavigation system.

The hand-held device may accommodate a database with POIs and with audiofiles containing spoken, e.g. narrated, information on some or all ofthe respective POIs.

The hand-held device may accommodate the text-to-speech processor forconverting text information on POIs into spoken information on the POIs.

The hand-held device may accommodate the interface of the personalnavigation system for connection with a Wide-Area-Network and/or aLocal-Area-Network.

For example, the hand-held device may have the wireless antenna,transmitter, and receiver of the personal communication system forcommunicating over a wireless network with a remote server accommodatinga database with information on POIs, e.g. including audio files withspoken information on some or all of the POIs. The wireless network maybe a mobile telephone network, such as the GSM network.

The hand-held device may accommodate the processor that is configuredfor requesting information on a particular Point-Of-Interest via theWide-Area-Network and/or Local-Area-Network, and for receiving theinformation via the network.

The hearing device may have a microphone for reception of spokencommands by the user, and the processor may be configured for decodingof the spoken commands and for controlling the personal navigationsystem to perform the actions defined by the respective spoken commands.

The hearing device may comprise an ambient microphone for receivingambient sound for user selectable transmission towards at least one ofthe ears of the user.

In the event that the hearing device provides a sound proof, orsubstantially, sound proof, transmission path for sound emitted by theloudspeaker(s) of the hearing device towards the ear(s) of the user, theuser may be acoustically disconnected in an undesirable way from thesurroundings. This may for example be dangerous when moving in traffic.

The hearing device may have a user interface, e.g. a push button, sothat the user can switch the microphone on and off as desired therebyconnecting or disconnecting the ambient microphone and one loudspeakerof the hearing device.

The hearing device may have a mixer with an input connected to an outputof the ambient microphone and another input connected to an output ofthe sound generator, and an output providing an audio signal that is aweighted combination of the two input audio signals.

The user input may further include means for user adjustment of theweights of the combination of the two input audio signals, such as adial, or a push button for incremental adjustment.

The hearing device may have a threshold detector for determining theloudness of the ambient signal received by the ambient microphone, andthe mixer may be configured for including the output of the ambientmicrophone signal in its output signal only when a certain threshold isexceeded by the loudness of the ambient signal.

Further ways of controlling audio signals from an ambient microphone anda voice microphone is disclosed in US 2011/0206217 A1.

The personal navigation system also has a GPS-unit for determining thegeographical position of the user based on satellite signals in thewell-known way. Hereby, the personal navigation system can provide theuser's current geographical position based on the GPS-unit and theorientation of the user's head based on data from the hearing device.

Throughout the present disclosure, the term GPS-unit is used todesignate a receiver of satellite signals of any satellite navigationsystem that provides location and time information anywhere on or nearthe Earth, such as the satellite navigation system maintained by theUnited States government and freely accessible to anyone with a GPSreceiver and typically designated “the GPS-system”, the Russian GLObalNAvigation Satellite System (GLONASS), the European Union Galileonavigation system, the Chinese Compass navigation system, the IndianRegional Navigational Satellite System, etc, and also includingaugmented GPS, such as StarFire, Omnistar, the Indian GPS Aided GeoAugmented Navigation (GAGAN), the European Geostationary NavigationOverlay Service (EGNOS), the Japanese Multi-functional SatelliteAugmentation System (MSAS), etc.

In augmented GPS, a network of ground-based reference stations measuresmall variations in the GPS satellites' signals, correction messages aresent to the GPS-system satellites that broadcast the correction messagesback to Earth, where augmented GPS-enabled receivers use the correctionswhile computing their positions to improve accuracy. The InternationalCivil Aviation Organization (ICAO) calls this type of system asatellite-based augmentation system (SBAS).

Like the inertial measurement unit, the GPS-unit may be accommodated inthe hearing device for determining the geographical position of theuser, when the user wears the hearing device in its intended operationalposition on the head, based on satellite signals in the well-known way.Hereby, the user's current position and orientation can be provided tothe user based on data from the hearing device.

Alternatively, the GPS-unit may be included in the hand-held device thatis interconnected with the hearing device. The hearing device mayaccommodate a GPS-antenna that is connected with the GPS-unit in thehand-held device, whereby reception of GPS-signals is improved inparticular in urban areas where, presently, reception of GPS-signals byhand-held GPS-units can be difficult.

The inertial measurement unit may also have a magnetic compass forexample in the form of a tri-axis magnetometer facilitatingdetermination of head yaw with relation to the magnetic field of theearth, e.g. with relation to Magnetic North.

The sound generator of the personal navigation system is connected foroutputting audio signals to the loudspeakers via the one or more pairsof filters with respective Head-Related Transfer Functions and connectedin parallel between the sound generator and the loudspeakers forgeneration of a binaural acoustic sound signal emitted towards theeardrums of the user. In this way, sound from the hearing device will beperceived by the user as coming from a sound source positioned in adirection corresponding to the respective Head-Related Transfer Functionof the current pair of filters.

The Head-Related Transfer Function of the pair of filters simulates thetransmission of sound from a sound source located in a specific positionto each of the two eardrums of the user.

Preferably, the one or more pairs of filters comprise digital filterswith registers holding the filter coefficients. Thus, the filtercoefficients of a selected Head-Related Transfer Function are loadedinto the appropriate pair of registers and the respective pair offilters operates to filter with transfer functions of the selectedHead-Related Transfer Function. In this way, several or all of theHead-Related Transfer Functions may be provided by a single pair offilters by loading appropriate filter coefficients into their registers.

The input to the user's auditory system consists of two signals, namelysound pressures at the left eardrum and sound pressures at the righteardrum, in the following termed the binaural sound signals. Thus, ifsound pressures are accurately reproduced at the eardrums, the humanauditory system will not be able to distinguish the reproduced soundpressures from sound pressures originated from a 3-dimensional spatialsound field.

It is not fully known how the human auditory system extracts informationabout distance and direction to a sound source, but it is known that thehuman auditory system uses a number of cues in this determination. Amongthe cues are spectral cues, reverberation cues, interaural timedifferences (ITD), interaural phase differences (IPD) and interaurallevel differences (ILD).

The transmission of a sound wave from a sound source positioned at agiven direction and distance in relation to the left and right ears ofthe listener is described in terms of two transfer functions, one forthe left ear and one for the right ear, that include any lineardistortion, such as coloration, interaural time differences andinteraural spectral differences. Such a set of two transfer functions,one for the left ear and one for the right ear, is called a Head-RelatedTransfer Function (HRTF). Each transfer function of the HRTF is definedas the ratio between a sound pressure p generated by a plane wave at aspecific point in or close to the appertaining ear canal (p_(L) in theleft ear canal and p_(R) in the right ear canal) in relation to areference. The reference traditionally chosen is the sound pressurep_(l) that would have been generated by a plane wave at a position rightin the middle of the head with the listener absent.

The HRTF changes with direction and distance of the sound source inrelation to the ears of the listener. It is possible to measure the HRTFfor any direction and distance and simulate the HRTF, e.g.electronically, e.g. by pair of filters. If such pair of filters areinserted in the signal path between a playback unit, such as a mediaplayer, e.g. an Ipod®, and headphones used by a listener, the listenerwill achieve the perception that the sounds generated by the headphonesoriginate from a sound source positioned at the distance and in thedirection as defined by the HRTF simulated by the pair of filters,because of the approximately true reproduction of the sound pressures inthe ears.

The HRTF contains all information relating to the sound transmission tothe ears of the listener, including diffraction around the head,reflections from shoulders, reflections in the ear canal, etc., andtherefore, due to the different anatomy of different individuals, theHRTFs are different for different individuals.

However, it is possible to provide general HRTFs which are sufficientlyclose to corresponding individual HRTFs for users in general to obtainthe same sense of direction of arrival of a sound signal that has beenfiltered with pair of filters with the general HRTFs as of a soundsignal that has been filtered with the corresponding individual HRTFs ofthe individual in question.

General HRTFs are disclosed in WO 93/22493.

For some directions of arrival, corresponding HRTFs may be constructedby approximation, for example by interpolating HRTFs corresponding toneighbouring angles of sound incidence, the interpolation being carriedout as a weighted average of neighbouring HRTFs, or an approximated HRTFcan be provided by adjustment of the linear phase of a neighbouring HTRFto obtain substantially the interaural time difference corresponding tothe direction of arrival for which the approximated HRTF is intended.

For convenience, the pair of transfer functions of a pair of filterssimulating an HRTF is also denoted a Head-Related Transfer Function eventhough the pair of filters can only approximate an HRTF.

Electronic simulation of the HRTFs by a pair of filters causes sound tobe reproduced by the hearing device in such a way that the userperceives sound sources to be localized outside the head in specificdirections. Thus, sound reproduced with pairs of filters with a HRTFmakes it possible to guide the user in a certain direction.

For example, sound can be reproduced with an HRTF corresponding to thedirection towards a desired geographical destination, so that the userperceives the sound source to be located and operated like a sonarbeacon at the desired geographical destination. Thus, the personalnavigation system utilizes a virtual sonar beacon located at the desiredgeographical destination to guide the user to the desired geographicaldestination. The virtual sonar beacon operates until the user reachesthe geographical position or is otherwise aborted by the user.

The sonar beacon may emit any sound suitable for guidance of the user,including music and speech.

In this way, the user is relieved from the task of watching a map inorder to follow a suitable route towards the desired geographicaldestination.

The user is also relieved from listening to spoken commands intending toguide the user along a suitable route towards the desired geographicaldestination.

Further, the user is free to explore the surroundings and for examplewalk along certain streets as desired, e.g. act on impulse, whilelistening to sound perceived to come from the direction toward thedesired geographical destination (also) to be visited, whereby the useris not restricted or urged to follow a specific route determined by thenavigation system.

The sound generator may output audio signals representing any type ofsound suitable for this purpose, such as speech, e.g. from an audiobook, radio, etc, music, tone sequences, etc.

The sound generator may output a tone sequence, e.g. of the samefrequency, or the frequency of the tones may be increased or decreasedwith distance to the desired geographical destination. Alternatively, oradditionally, the repetition rate of the tones may be increased ordecreased with distance to the desired geographical destination.

The user may for example decide to listen to a radio station whilewalking, and the sound generator generates audio signals originatingfrom the desired radio station filtered by the HRTF in question, so thatthe user perceives to hear the desired radio station as a sonar beaconlocated at the desired geographical destination to be visited at somepoint in time.

The user may decide to follow a certain route determined and suggestedby the personal navigation system, and in this case the processorcontrols the pair of filters so that the audio signals from the soundgenerator are filtered by HRTFs corresponding to desired directionsalong streets or other paths along the determined route. Changes inindicated directions will be experienced at junctions and may beindicated by increased loudness or pitch of the sound. Also in thiscase, the user is relieved from having to consult a map in order to beable to follow the determined route.

The personal navigation system may be operated without a visual display,and thus without displayed maps to be consulted by the user, rather theuser specifies desired geographical destinations with spoken commandsand receives aural guidance by sound emitted by the hearing device insuch a way that the sound is perceived by the user as coming from thedirection towards the desired geographical destination.

Thus, the personal navigation system may operate without a hand-helddevice, and rely on aural user interface using spoken commands and auralguidance, including spoken messages.

In this case, the personal navigation system comprises a hearing deviceconfigured to be head worn and having

loudspeakers for emission of sound towards the ears of a user andaccommodating an inertial measurement unit positioned for determininghead yaw, when the user wears the hearing device in its intendedoperational position on the user's head,a GPS unit for determining the geographical position of the user,a sound generator connected for outputting audio signals to theloudspeakers,pair of filters with Head-Related Transfer Functions connected inparallel between the sound generator and the loudspeakers for generationof a binaural acoustic sound signal emitted towards the eardrums of theuser and perceived by the user as coming from a sound source positionedin a direction corresponding to the respective Head-Related TransferFunction, anda processor configured fordetermining a direction towards a desired geographical destination withrelation to the determined geographical position and head yaw of theuser,controlling the sound generator to output audio signals, andselecting a Head-Related Transfer function for the pair of filterscorresponding to the determined direction towards the desiredgeographical destination so that the user hears sound arriving from thedetermined direction.

In absence of GPS-signal, e.g. when buildings or terrain block thesatellite signals, the personal navigation system may continue itsoperation relying on data from the inertial measurement unit of thehearing device utilising dead reckoning as is well-known from Inertialnavigation systems in general. The processor uses information from gyrosand accelerometers of the inertial measurement unit of the hearingdevice to calculate speed and direction of travel as a function of timeand integrates to determine geographical positions of the user with thelatest determined position based on GPS-signals as a starting point,until appropriate GPS-signal reception is resumed.

In accordance with some embodiments, a navigation system includes ahearing device configured to be head worn and having loudspeakers foremission of sound towards ears of a user; a GPS unit for determining ageographical position of the system; a sound generator connected foroutputting audio signals to the loudspeakers; and a processor configuredfor selecting Points-Of-Interest in a vicinity of the system, andcontrolling the sound generator to output the audio signals thatrepresents spoken information on the selected Points-Of-Interest insequence.

In accordance with other embodiments, a method of navigation includes:determining a geographical position of a person with a GPS unit;selecting Points-Of-Interests in a vicinity of the user; and controllinga loudspeaker worn by the user to output spoken information on theselected Points-Of-Interests.

Other and further aspects and features will be evident from reading thefollowing detailed description of the embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate the design and utility of embodiments, in whichsimilar elements are referred to by common reference numerals. Thesedrawings are not necessarily drawn to scale. In order to betterappreciate how the above-recited and other advantages and objects areobtained, a more particular description of the embodiments will berendered, which are illustrated in the accompanying drawings. Thesedrawings depict only typical embodiments and are not therefore to beconsidered limiting of the scope of the claims. Below, the embodimentswill be described in more detail with reference to the drawings, wherein

FIG. 1 shows a hearing device with an inertial measurement unit,

FIG. 2 shows (a) a head reference coordinate system and (b) head yaw,

FIG. 3 shows (a) head pitch and (b) head roll,

FIG. 4 is a block diagram of one embodiment of the new personalnavigation system,

FIG. 5 illustrates one exemplary use of the new personal navigationsystem, and

FIG. 6 schematically illustrates the operation of the system,

FIG. 7 schematically illustrates an example of the operation of thesystem, and

FIG. 8 schematically illustrates another example of the operation of thesystem.

DETAILED DESCRIPTION

Various embodiments are described hereinafter with reference to thefigures. It should be noted that the figures are not drawn to scale andthat elements of similar structures or functions are represented by likereference numerals throughout the figures. It should also be noted thatthe figures are only intended to facilitate the description of theembodiments. They are not intended as an exhaustive description of theclaimed invention or as a limitation on the scope of the claimedinvention. In addition, an illustrated embodiment needs not have all theaspects or advantages shown. An aspect or an advantage described inconjunction with a particular embodiment is not necessarily limited tothat embodiment and can be practiced in any other embodiments even ifnot so illustrated, or explicitly described.

The new personal navigation system 10 will now be described more fullyhereinafter with reference to the accompanying drawings, in whichvarious embodiments are shown. The new personal navigation system 10 maybe embodied in different forms not shown in the accompanying drawingsand should not be construed as limited to the embodiments and examplesset forth herein.

FIG. 1 shows an exemplary hearing device 12 of the personal navigationsystem 10, having a headband 17 carrying two earphones 15A, 15B similarto a conventional corded headset with two earphones 15A, 15Binterconnected by a headband 17.

Each earphone 15A, 15B of the illustrated hearing device 12 comprises anear pad 18 for enhancing the user comfort and blocking out ambientsounds during listening or two-way communication.

A microphone boom 19 with a voice microphone 4 at the free end extendsfrom the first earphone 15A. The microphone 4 is used for picking up theuser's voice e.g. during two-way communication via a mobile phonenetwork and/or for reception of user commands to the personal navigationsystem 10.

The housing of the first earphone 15A comprises a first ambientmicrophone 6A and the housing of the second earphone 15B comprises asecond ambient microphone 6B.

The ambient microphones 6A, 6B are provided for picking up ambientsounds, which the user can select to mix with the sound received from ahand-held device 14 (not shown), e.g. a mobile phone, a media player,such as an Ipod, a GPS-unit, a smart phone, a remote control for thehearing device 12, etc.

The user can select to mix ambient sounds picked up by the ambientmicrophones 6A, 6B with sound received from the hand-held device 14 (notshown) as already mentioned.

When mixed-in, sound from the first ambient microphone 6A is directed tothe speaker of the first earphone 15A, and sound from the second ambientmicrophone 6B is directed to the speaker of the second earphone 15B.

A cord 30 extends from the first earphone 15A to the hand-held device 14(not shown).

A Bluetooth transceiver in the earphone 15 is wirelessly connected by aBluetooth link 20 to a Bluetooth transceiver in the hand-held device 14(not shown).

The cord 30 may be used for transmission of audio signals from themicrophones 4, 6A, 6B to the hand-held device 14 (not shown), while theBluetooth network may be used for data transmission of data from theinertial measurement unit to the hand-held device 14 (not shown) andcommands from the hand-held device 14 (not shown) to the hearing device12, such as turn a selected microphone 4, 6A, 6B on or off.

A similar hearing device 12 may be provided without a Bluetoothtransceiver so that the cord 30 is used for both transmission of audiosignals and data signals; or, a similar hearing device 12 may beprovided without a cord, so that a Bluetooth network is used for bothtransmissions of audio signals and data signals.

A similar hearing device 12 may be provided without the microphone boom19, whereby the microphone 4 is provided in a housing on the cord as iswell-known from prior art headsets.

A similar hearing device 12 may be provided without the microphone boom19 and microphone 4 functioning as a headphone instead of a headset.

An inertial measurement unit 50 is accommodated in a housing mounted onor integrated with the headband 17 and interconnected with components inthe earphone housing 16 through wires running internally in the headband17 between the inertial measurement unit 50 and the earphone 15.

The user interface of the hearing device 12 is not visible, but mayinclude one or more push buttons, and/or one or more dials as iswell-known from conventional headsets.

The orientation of the head of the user is defined as the orientation ofa head reference coordinate system with relation to a referencecoordinate system with a vertical axis and two horizontal axes at thecurrent location of the user.

FIG. 2( a) shows a head reference coordinate system 100 that is definedwith its centre 110 located at the centre of the user's head 32, whichis defined as the midpoint 110 of a line 120 drawn between therespective centres of the eardrums (not shown) of the left and rightears 33, 34 of the user.

The x-axis 130 of the head reference coordinate system 100 is pointingahead through a centre of the nose 35 of the user, its y-axis 112 ispointing towards the left ear 33 through the centre of the left eardrum(not shown), and its z-axis 140 is pointing upwards.

FIG. 2( b) illustrates the definition of head yaw 150. Head yaw 150 isthe angle between the current x-axis' projection x′ 132 onto ahorizontal plane 160 at the location of the user, and a horizontalreference direction 170, such as Magnetic North or True North.

FIG. 3( a) illustrates the definition of head pitch 180. Head pitch 180is the angle between the current x-axis 130 and the horizontal plane160.

FIG. 3( b) illustrates the definition of head roll 190. Head roll 190 isthe angle between the y-axis and the horizontal plane.

FIG. 4 shows a block diagram of a new personal navigation system 10comprising a hearing device 12 and a hand-held device 14.

The various components of the system 12 may be distributed otherwisebetween the hearing device 12 and the hand-held device 14. For example,the hand-held device 14 may accommodate the GPS-receiver 58. Anothersystem 10 may not have a hand-held device 14 so that all the componentsof the system 10 are accommodated in the hearing device 12. The system10 without a hand-held device 14 does not have a display, and speechsynthesis is used to issue messages and instructions to the user andspeech recognition is used to receive spoken commands from the user.

The illustrated personal navigation system 10 comprises a hearing device12 comprising electronic components including two loudspeakers 15A, 15Bfor emission of sound towards the ears of the user (not shown), when thehearing device 12 is worn by the user in its intended operationalposition on the user's head.

It should be noted that in addition to the hearing device 12 shown inFIG. 1, the hearing device 12 may be of any known type including anEar-Hook, In-Ear, On-Ear, Over-the-Ear, Behind-the-Neck, Helmet,Headguard, etc, headset, headphone, earphone, ear defenders, earmuffs,etc.

Further, the hearing device 12 may be a binaural hearing aid, such as aBTE, a RIE, an ITE, an ITC, a CIC, etc, binaural hearing aid.

The illustrated hearing device 12 has a voice microphone 4 e.g.accommodated in an earphone housing or provided at the free end of amicrophone boom mounted to an earphone housing.

The hearing device 12 further has one or two ambient microphones 6A, 6B,e.g. at each ear, for picking up ambient sounds.

The hearing device 12 has an inertial measurement unit 50 positioned fordetermining head yaw, head pitch, and head roll, when the user wears thehearing device 12 in its intended operational position on the user'shead.

The illustrated inertial measurement unit 50 has tri-axis MEMS gyros 56that provide information on head yaw, head pitch, and head roll inaddition to tri-axis accelerometers 54 that provide information on threedimensional displacement of the hearing device 12.

The hearing device 12 also has a GPS-unit 58 for determining thegeographical position of the user, when the user wears the hearingdevice 12 in its intended operational position on the head, based onsatellite signals in the well-known way. Hereby, the user's currentposition and orientation can be provided to the user based on data fromthe hearing device 12.

Optionally, the hearing device 12 accommodates a GPS-antenna configuredfor reception of GPS-signals, whereby reception of GPS-signals isimproved in particular in urban areas where, presently, reception ofGPS-signals can be difficult.

In a hearing device 12 without the GPS-unit 58, the hearing device 12has an interface for connection of the GPS-antenna with an externalGPS-unit, e.g. a hand-held GPS-unit, whereby reception of GPS-signals bythe hand-held GPS-unit is improved in particular in urban areas where,presently, reception of GPS-signals by hand-held GPS-units can bedifficult.

The illustrated inertial measurement unit 50 also has a magnetic compassin the form of a tri-axis magnetometer 52 facilitating determination ofhead yaw with relation to the magnetic field of the earth, e.g. withrelation to Magnetic North.

The hand-held device 14 of the personal navigation system 10 has aprocessor 80 with input/output ports connected to the sensors of theinertial measurement unit 50, and configured for determining andoutputting values for head yaw, head pitch, and head roll, when the userwears the hearing device 12 in its intended operational position on theuser's head.

The processor 80 may further have inputs connected to accelerometers ofthe inertial measurement unit, and configured for determining andoutputting values for displacement in one, two or three dimensions ofthe user when the user wears the hearing device 12 in its intendedoperational position on the user's head, for example to be used for deadreckoning in the event that GPS-signals are lost.

Thus, the illustrated personal navigation system 10 is equipped with acomplete attitude heading reference system (AHRS) for determination ofthe orientation of the user's head that has MEMS gyroscopes,accelerometers and magnetometers on all three axes. The processorprovides digital values of the head yaw, head pitch, and head roll basedon the sensor data.

The hearing device 12 has a data interface 20 for transmission of datafrom the inertial measurement unit to the processor 80 of the hand-helddevice 14, e.g. a smart phone with corresponding data interface. Thedata interface 20 is a Bluetooth Low Energy interface.

The hearing device 12 further has a conventional wired audio interface28 for audio signals from the voice microphone 4, and for audio signalsto the loudspeakers 15A, 15B for interconnection with the hand-helddevice 14 with corresponding audio interface 28.

This combination of a low power wireless interface for datacommunication and a wired interface for audio signals provides asuperior combination of high quality sound reproduction and low powerconsumption of the personal navigation system 10.

The hearing device 12 has a user interface 21, e.g. with push buttonsand dials as is well-known from conventional headsets, for user controland adjustment of the hearing device 12 and possibly the hand-helddevice 14 interconnected with the hearing device 12, e.g. for selectionof media to be played.

The hand-held device 14 receives head yaw from the inertial measurementunit of the hearing device 12 through the Bluetooth Low Energy wirelessinterface. With this information, the hand-held device 14 can displaymaps on its display in accordance with orientation of the head of theuser as projected onto a horizontal plane, i.e. typically correspondingto the plane of the map. For example, the map may automatically bedisplayed with the position of the user at a central position of thedisplay, and the current head x-axis pointing upwards.

The user may use the user interface of the hand-held device 14 to inputinformation on a geographical position the user desires to visit in away well-known from prior art hand-held GPS-units.

The hand-held device 14 may display maps with a suggested route to thedesired geographical destination as a supplement to the aural guidanceprovided through the hearing device 12.

The hand-held device 14 may further transmit spoken guiding instructionsto the hearing device 12 through the audio interface 28 as is well-knownin the art, supplementing the other audio signals provided to thehearing device 12.

In addition, the microphone of hearing device 12 may be used forreception of spoken commands by the user, and the processor 80 may beconfigured for speech recognition, i.e. decoding of the spoken commands,and for controlling the personal navigation system 10 to perform actionsdefined by respective spoken commands.

The hand-held device 14 filters the output of a sound generator 24 ofthe hand-held device 14 with a pair of filters 60, 62 with an HRTF intotwo output audio signals, one for the left ear and one for the rightear, corresponding to the filtering of the HRTF of a direction in whichthe user should travel in order to visit a desired geographicaldestination.

This filtering process causes sound reproduced by the hearing device 12to be perceived by the user as coming from a sound source localizedoutside the head from a direction corresponding to the HRTF in question,i.e. from a virtual sonar beacon located at the desired geographicaldestination.

In this way, the user is relieved from the task of watching a map inorder to follow a suitable route towards the desired geographicaldestination.

The user is also relieved from listening to spoken commands intending toguide the user along a suitable route towards the desired geographicaldestination.

Further, the user is free to explore the surroundings and for examplewalk along certain streets as desired, e.g. act on impulse, whilelistening to sound perceived to come from the direction toward thedesired geographical destination (also) to be visited, whereby the useris not restricted to follow a specific route determined by the personalnavigation system 10.

The sound generator 24 may output audio signals representing any type ofsound suitable for this purpose, such as speech, e.g. from an audiobook, radio, etc, music, tone sequences, etc.

The user may for example decide to listen to a radio station whilewalking, and the sound generator 24 generates audio signals reproducingthe signals originating from the desired radio station filtered by pairof filters 60, 62 with the HRTFs in question, so that the user perceivesto hear the desired music from the direction towards the desiredgeographical destination to be visited at some point in time.

At some point in time, the user may decide to follow a certain routedetermined and suggested by the personal navigation system 10, and inthis case the processor controls the HRTF filters so that the audiosignals from the sound generator 24 are filtered by HRTFs correspondingto desired directions along streets or other paths along the determinedroute. Changes in indicated directions will be experienced at junctionsand may be indicated by increased loudness or pitch of the sound. Alsoin this case, the user is relieved from having to visually consult a mapin order to be able to follow the determined route.

In the event that the processor controls the sound generator 24 tooutput a tone sequence, e.g. of the same frequency, the frequency of thetones may be increased or decreased with distance to the desiredgeographical destination. Alternatively, or additionally, the repetitionrate of the tones may be increased or decreased with distance to thedesired geographical destination.

The personal navigation system 10 may be operated without using thevisual display, i.e. without the user consulting displayed maps, ratherthe user specifies desired geographical destinations with spokencommands and receives aural guidance by sound emitted by the hearingdevice 12 in such a way that the sound is perceived by the user ascoming from the direction towards the desired geographical destination.

FIG. 5 illustrates the configuration and operation of an example of thenew personal navigation system 10 shown in FIG. 4, with the hearingdevice 12 together with a hand-held device 14, which in the illustratedexample is a smart phone 200, e.g. an Iphone, an Android phone, etc,with a personal navigation app containing instructions for the processorof the smart phone to perform the operations of the processor 80 of thepersonal navigation system 10 and of the pair of filters 60, 62 with anHRTF. The hearing device 12 is connected to the smart phone 200 with achord 30 providing a wired audio interface 28 between the two units 10,200 for transmission of speech and music from the smart phone 200 to thehearing device 12, and speech from the voice microphone 4 (not shown) tothe smart phone 200 as is well-known in the art.

As indicated in FIG. 5 by the various exemplary GPS-images 210 displayedon the smart phone display 220, the personal navigation app is executedby the smart phone in addition to other tasks that the user selects tobe performed simultaneously by the smart phone 200, such as playingmusic, and performing telephone calls when required.

The personal navigation app configures the smart phone 200 for datacommunication with the hearing device 12 through a Bluetooth Low Energywireless interface 20 available in the smart phone 200 and the hearingdevice 12, e.g. for reception of head yaw from the inertial measurementunit 50 of the hearing device 12. In this way, the personal navigationapp can control display of maps on the display of the smart phone 200 inaccordance with orientation of the head of the user as projected onto ahorizontal plane, i.e. typically corresponding to the plane of the map.For example, the map may be displayed with the position of the user at acentral position of the display, and the head x-axis pointing upwards.

The personal navigation system 10 operates to position a virtual sonarbeacon at a desired geographical location, whereby a guiding soundsignal is transmitted to the ears of the user that is perceived by theuser to arrive from a certain direction in which the user should travelin order to visit the desired geographical location. The guiding soundis generated by a sound generator 24 of the smart phone 200, and theoutput of the sound generator 24 is filtered in parallel with the pairof filters 60, 62 of the smart phone 200 having an HRTF so that an audiosignal for the left ear and an audio signal for the right ear aregenerated. The filter functions of the two filters approximate the HRTFcorresponding to the direction from the user to the desired geographicallocation taking the yaw of the head of the user into account.

The user may calibrate directional information by indicating when his orher head x-axis is kept in a known direction, for example by pushing acertain push button when looking due North, typically True North. Theuser may obtain information on the direction due True North, e.g. fromthe position of the Sun on a certain time of day, or the position of theNorth Star, or from a map, etc.

The user may calibrate directional information by indicating when his orher head x-axis is kept in a known direction, for example by pushing acertain push button when looking due North, typically True North. Theuser may obtain information on the direction due True North, e.g. fromthe position of the Sun on a certain time of day, or the position of theNorth Star, or from a map, etc.

At any time during use of the personal navigation system, the user mayuse the user interface to request a sequential spoken presentation ofPOIs proximate the user, e.g. by pushing a specific button located atthe hearing device 12.

For example, the user may arrive at a town square as schematicallyillustrated in FIG. 6, with various POIs. As indicated in FIG. 6, theuser has requested the personal navigation system 10 to provide anintroduction to POIs at the town square, and possibly, the user hasspecified the types of POIs to be included in the introduction, e.g.historical sites. In response to the user request, the personalnavigation system has identified the historical POIs at or proximate thetown square and sequentially narrates information on the identified POIs1, 2, 3, and 4.

The narrated information is communicated with the hearing device,preferably with a sense of direction so that narrated informationrelating to a specific site proximate the user will be perceived by theuser to be emitted by a sound source located at the site in question sothat the narrator will sequentially be perceived to be positioned at therespective POIs.

In this way, the user is provided with spatial knowledge about thesurroundings and the need to visually consult a display of thesurroundings is minimized making it easy and convenient for the user tonavigate to geographical locations, the user desires to see or visit.

During or after the narrated presentation, the user may request thepersonal navigation system to guide the user to a selected geographicalposition, such as a selected POI from the POIs just presented insequence to the user. The processor will then determine a directiontowards a selected geographical destination and guide the user towardsthat geographical destination as previously described.

The smart phone 200 may contain a database of POIs as is way well-knownin conventional smart phones.

Some or all of the POI records of the database of the personalnavigation system include audio files with spoken information on therespective POI.

Alternatively, or additionally, the personal navigation system may haveaccess to remote servers hosting databases on POIs, e.g. through aWide-Area-Network, or a Local Area Network, e.g. providing access to theInternet.

Thus, the personal navigation system may have a wireless antenna,transmitter, and receiver for communicating over a wireless network witha remote server accommodating a database with information on POIs, e.g.including audio files with spoken information on some or all of thePOIs. The wireless network may be a mobile telephone network, such as aGSM network.

The wireless network may provide a link through an Internet gateway tothe Internet.

The personal navigation system may transmit the current position of thesystem to the remote server and requesting information on nearby POIs,preferably of one or more selected categories, and preferably sequencedin accordance with a selected rule of priority, such as proximity,popularity, user ratings, professional ratings, cost of entrance,opening hours with relation to actual time, etc. A maximum number ofPOIs may also be specified.

The server searches for matching POIs and transmits the matchingrecords, e.g. including audio files, to the personal navigation systemthat sequentially presents spoken information on the matching POIs withthe hearing instrument.

The spoken information may include opening hours of POIs, time table ofupcoming venues of POIs, etc.

The smart phone may be configured request navigation tasks to beperformed by a remote navigation enabled server whereby the smart phonecommunicates position data of the current position, e.g. currentlongitude, latitude; or, the received satellite signals, and positiondata of a destination, e.g. longitude, latitude; or street address,etc., to the navigation enabled server that performs the requestednavigation tasks and transmits resulting data to the smart phone forpresentation to the user.

FIG. 7 illustrates an example of use of the personal navigation system,where the user has taken the metro (metro station indicated by an arrow)to the town square: “Kongens Nytorv” in Copenhagen. The user has walkedfrom the metro station to the town square and is presently looking atthe statue located at the centre of the square as indicated in FIG. 7.The user has requested a presentation of nearby POIs made available onthe Internet by Wikipedia. The available POIs are indicated by capitalletter W in a square frame. Short text introductions to the availablePOIs are acquired from Wikipedia by the personal navigation system andconverted into speech by the text-to-speech converter of the smartphone. The presentations are prioritized by proximity, i.e. the POIclosest to the user is presented first, then the second closest POI,etc.

As indicated by the dashed line, the user perceives to hear thepresentations made by a narrator positioned at the respective POIswhereby the user is informed on the directions towards each of thepresented POIs.

In the illustrated example, the user has limited the number of presentedPOIs to four.

FIG. 8 illustrates that the user subsequently to the presentation ofhistorical sites at the square, has requested the personal navigationsystem to present nearby restaurants (indicated in circles) as providedby another organisation, e.g. The official tourism site of Denmark, or,the Michelin Guide, etc.

Although particular embodiments have been shown and described, it willbe understood that they are not intended to limit the claimedinventions, and it will be obvious to those skilled in the art thatvarious changes and modifications may be made without departing from thespirit and scope of the claimed inventions. The specification anddrawings are, accordingly, to be regarded in an illustrative rather thanrestrictive sense. The claimed inventions are intended to coveralternatives, modifications, and equivalents.

1. A navigation system comprising: a hearing device configured to behead worn and having loudspeakers for emission of sound towards ears ofa user; a GPS unit for determining a geographical position of thesystem; a sound generator connected for outputting audio signals to theloudspeakers; and a processor configured for: selectingPoints-Of-Interest in a vicinity of the system, and controlling thesound generator to output the audio signals that represents spokeninformation on the selected Points-Of-Interest in sequence.
 2. Thenavigation system according to claim 1, further comprising: a pair offilters with a Head-Related Transfer Function connected in parallelbetween the sound generator and the loudspeakers for generation of abinaural acoustic sound signals emitted towards eardrums of the user andperceived by the user as coming from a sound source positioned in adirection corresponding to the Head-Related Transfer Function.
 3. Thenavigation system according to claim 1, wherein the hearing deviceaccommodates an inertial measurement unit for determining head yaw, whenthe user wears the hearing device in its intended operational positionon a head of the user; and the processor is configured for determiningrespective directions towards the selected Points-Of-Interest withrelation to the determined geographical position and the head yaw of theuser, selecting respective Head-Related Transfer Functions correspondingto the determined directions, and controlling the sound generator forsequentially outputting the audio signals that represent the spokeninformation on the selected Points-Of-Interest in sequence through apair of filters with the selected respective Head-Related TransferFunctions so that the user hears the spoken information on thePoints-Of-Interest sequentially from the respective directions towardsthe Points-Of-Interest.
 4. The navigation system according to claim 1,wherein the selected Points-Of-Interest are selected from a subset ofPoints-Of-Interest specified by the user.
 5. The navigation systemaccording to claim 1, further comprising a database with information onPoints-Of-Interest.
 6. The navigation system according to claim 1,further comprising an interface for connection with a Wide-Area-Network.7. The navigation system according to claim 6, wherein the processor isconfigured for requesting information on one of the Points-Of-Interestvia the Wide-Area-Network and for receiving the requested informationvia the Wide-Area-Network.
 8. The navigation system according to claim1, wherein the processor is configured to perform word recognition andto perform speech synthesis for generation of the audio signals thatrepresent spoken information on the selected Points-Of-Interest based ontext information on the selected Points-Of-Interest.
 9. The navigationsystem according to claim 1, further comprising a user interfaceconfigured for reception of spoken user commands.
 10. The navigationsystem according to claim 1, further comprising a hand-held devicecommunicatively coupling with the hearing device.
 11. The navigationsystem according to claim 10, wherein the hand-held device accommodatesthe sound generator and a pair of filters with Head-Related Transferfunctions.
 12. The navigation system according to claim 10, wherein thehand-held device accommodates a user interface configured for receptionof spoken user commands.
 13. The navigation system according to claim10, wherein the hand-held device comprises a display, and a processorconfigured to display a map on the display with an indication of thedetermined geographical position and a head yaw of the user, and iconsof the selected Points-Of-Interest at respective geographical positionsof the selected Points-Of-Interest.
 14. The navigation system accordingto claim 10, wherein the hand-held device accommodates the GPS unit. 15.The navigation system according to claim 10, further comprising awireless connection for communicating signals between the hand-helddevice and the hearing device.
 16. The navigation system according toclaim 10, further comprising a wired connection for communicatingsignals between the hand-held device and the hearing device.
 17. Thenavigation system according to claim 16, wherein the audio signals aretransmitted from the hand-held device to the hearing device with thewired connection, and wherein sensor data is transmitted from thehearing device to the hand-held device with a wireless connection.
 18. Amethod of navigation comprising: determining a geographical position ofa person with a GPS unit; selecting Points-Of-Interests in a vicinity ofthe user; and controlling a loudspeaker worn by the user to outputspoken information on the selected Points-Of-Interests.